Alaska Native children are disproportionately affected by early childhood caries, compared to all U.S. children. Dental care needs for adults and children in rural Alaska far exceed the acute care and prevention resources available. As a result,, there is a high level of dental morbidity present among adults that likely contributes to early transmission of mutants streptococci (MS) from adult caregivers to infants in the household. Furthermore, the cultural practice of per- mastication of solid food for infant feeding amplifies the transmission of oral secretions from adult to child. The prevention of early MS acquisition and subsequent caries in infants and toddlers required efforts starting at birth. Since Alaska Natives are a rural population at high risk for caries, interruption of vertical transmission of MS using a combination of improved oral hygiene practice, and topical antimicrobials and bacteriostatic agents may be an ideal prevention strategy for childhood caries. Chlorhexidine and xylitol are two agents that have been shown to reduce dental decay and MS counts. The specific aim of this proposal is to conduct a community based, randomized blinded trial to determine if the serial use of chlorhexidine and xylitol in 250 mothers will reduce the vertical transmission of caries between Alaska Native mothers and infants. The Yukon-Kuskokwim (YK) Delta of southwestern Alaska is the site of the study. We hypothesize that a two week period of twice-daily chlorhexidine mouthwash use prior to deliver followed by a subsequent two year period of maternal xylitol gum use, will lead to a significant reduction in the age-specific prevalence of early childhood caries at 12 and 24 months of age among the offspring of mothers in the intervention group, compared to control group mothers. We also hypothesize that, compared to controls, mothers and children in the intervention group will have significant reductions in oral MS counts at each follow-up interval. If proven successful, this intervention could have a significant impact on the prevalence of caries among young Alaska Native children and other population groups at high risk for childhood caries.